Isler, who stands 1.80 m (5 ft 11 in), competed as Miss Guárico, one of 24 finalists in her country’s national beauty pageant Miss Venezuela 2012, held on August 30, 2012 in Caracas, where she obtained the Miss Elegance award and became the ninth Miss Venezuela winner from Guárico, gaining the right to represent her country in Miss Universe.

After being crowned on November 9, 2013 in Moscow, Isler was interviewed by numerous prominent international media outlets.

On November 10, 2013, Isler participated in the presentation of Yamamay’s million dollar swimsuit at Crowne Plaza hotel in Moscow.

On November 21, 2013, she served as a presenter at the Latin Grammy Awards in Las Vegas with Illya Kuryaki and the Valderramas. Isler attended Elizabeth Glaser Pediatric AIDS Foundation’s Global Impact award Gala Dinner honoring Hillary Clinton at Best Buy Theater on December 3, 2013 in New York City.

On December 4, 2013, she attended the 81st annual Rockefeller Center Christmas Tree Lighting Ceremony at Rockefeller Center in New York City. On December 11, 2013, Isler traveled to Venezuela on an unofficial visit to enjoy Christmas with her family.

She traveled to Bali, Indonesia on January 7, 2014, where she filmed a publicity appearance for YOU•C1000. On January 17, 2014, Isler traveled to Cancún, Mexico for a photoshoot for Yamamay with Fadil Berisha. On January 26, 2014, she traveled to Indonesia again to assist in the crowning of Puteri Indonesia 2014 (Miss Universe Indonesia). Isler attended New York Fashion Week in February 2014. On February 14, 2013, she attended the Valentine’s Day Luncheon to Benefit Rush’s Education Programs, and three days later, she attended the CHCF’s “Countdown to A Slice of Latin America” Gala in New York.

On February 27, 2014, Isler participated in the Miss Russia 2014 press conference in Moscow, Russia, with Megan Young (Miss World) and Elmira Abdrazakova (Miss Russia). She was a judge at the Miss Russia 2014 pageant. Isler traveled to Miami on March 7, 2014 to participate in the Cadillac Championship Fashion Show. On March 8, 2014, she attended Emin Agalarov’s concert, also in Miami.

In March 2014, Isler visited the Philippines to raise funds for the Yolanda typhoon victims in Palawan and to help crown the winners of Binibining Pilipinas 2014 on March 30, 2014. On April 8, 2014, Isler travelled to Casablanca, Morocco to promote Peugeot 308 and walk in Casablanca Fashion Week.

During a special ceremony at Macy’s Herald Square, in New York, on April 16, 2014, Isler was named the new Madrina of the Latino Commission on AIDS, to welcome her as an international spokesperson to help deliver their message of HIV prevention. On April 24, 2014, she served as a presenter at the Billboard Latin Music Awards in Miami with David Chocarro. Isler attended the 11th Annual Project Sunshine benefit celebration at The Waldorf-Astoria Hotel on April 29, 2014 in New York City.

On April 30, 2014, Isler spoke on Capitol Hill in Washington, D.C. in support of amfAR, The Foundation for AIDS Research. The organization was founded by Elizabeth Taylor and is one of the world’s leading nonprofit organizations dedicated to HIV/AIDS research, prevention, education, and advocacy. Isler attended Operation Smile’s Smile Event at Cipriani Wall Street on May 1, 2014 in New York City. On May 8, 2014, Isler attended the 6th annual NFL Draft fundraiser Beyond the Boroughs at Dream Downtown in New York City.

Isler traveled to Curaçao on May 9, 2014, for the Miss Universe Curaçao 2014 designers night. On May 11, 2014, she attended the People en Español Los 50 Mas Bellos party at Club Capitale in New York City. As a Project Sunshine supporter, Isler participated in BTIG’s 12th annual Commissions for Charity Day at BTIG’s trading floor on May 13, 2014 in New York City. Isler attended the 2014 Telemundo Upfront at Frederick P. Rose Hall, Jazz at Lincoln Center the same day in New York City.

On May 17 and May 18, 2014, Isler walked the runway for Yamamay for Miss Universe swimsuits and Sherri Hill at Miami Fashion Week, held at the Miami Convention Center, Miami Beach. She attended El Museo’s Gala 2014 at Cipriani 42nd Street on May 21, 2014 in New York City. In May 2014, Isler was invited to the annual party parade in Machala, Ecuador. Isler attended the 2014 CFDA fashion awards at Alice Tully Hall, Lincoln Center on June 2, 2014 in New York City. In June 2014, she visited Baton Rouge, Louisiana to help crown the winner of Miss USA 2014 on June 8, 2014. Isler attended the amfAR Inspiration Gala New York 2014 at The Plaza Hotel on June 10, 2014 in New York City.

In June 2014, Isler traveled to Las Vegas for the Las Vegas Licensing Expo, with Nia Sanchez (Miss USA 2014). Isler attended Tammy New York special screening at Landmark Sunshine Cinema on June 26, 2014 in New York City. In July 2014, Isler visited Austria to help crown the winners of Miss Austria on July 3, 2014. She was a judge at Miss Austria pageant. Afterwards, she toured several countries in Eastern and Central Europe including the Czech Republic and Slovakia. Isler attended the 4th Annual St Mary’s event on July 17, 2014, at STK Rooftop in New York City. On July 18, 2014, Isler visited Baku, Azerbaijan, with Paula Shugart, President of Miss Universe Organization. Isler attended the OCRF’s 17th Annual Super Saturday hosted by Kelly Ripa And Donna Karan on July 26, 2014 in New York City. She attended the 15th annual Art for Life Gala hosted by Russell and Danny Simmons at Fairview Farms on July 26, 2014 in Water Mill, New York. On July 31, 2014, Isler traveled to the Bahamas to help the crown the winner of Miss Teen USA 2014.

On August 17, 2014, she traveled to the Dominican Republic to assist in the crowning of Miss Dominican Republic 2014.

On September 3, 2014, Isler attended the general audience of Pope Francis in Vatican City. She carried a Venezuelan flag and kissed the Pope’s hand in their brief encounter. She said that the visit made her feel blessed, and added, “I can only say that I am immensely grateful and happy.”

In September 2014, Isler joined Nia Sanchez and K. Lee Graham at the Mercedes Benz Fashion Week at Lincoln Center in New York City, where she met fellow Miss Universes Dayana Mendoza and Stefania Fernandez, both from Venezuela. She attended the Leaders’ Forum on Women Leading the Way: Raising Ambition for Climate Action at the United Nations.

On October 3, 2014, Isler joined Doral Mayor and Council, Donald Trump and Paula M. Shugart for the biannouncement of the 63rd Miss Universe 2014 Pageant at Trump National Doral Resort in Doral, Florida. On October 7, 2014, Isler returned to her home in Venezuela, and attended to the Miss Venezuela 2014 pageant in Caracas.

On January 25, 2015, Isler passed her title to Paulina Vega, Miss Colombia 2014 at the conclusion of the 63rd Miss Universe Pageant at FIU Arena, Miami, Florida.

Isler personally launched and is CEO of the Universe of Blessings Fund, a 501(c)(3) organization, which seeks to empower young women and girls and decrease the rates of adolescent pregnancy and maternal mortality, issues which are especially problematic in her native Venezuela. Deeply concerned about the victims of human trafficking and its devastating impact on young women, Isler is an ambassador for the Scalabrini International Migration Network. In addition, she is constructing a program which implements a values-based curricula designed to prepare young adults in Venezuela to realize their full potential, both personally and professionally, by providing critical life skills and vocational skills. She has been named after in many countries including Uganda where a newly born was named Namajja Hailey Gabriela. Namajja Hailey Gabriela was born on 14,February, 2019 to Dr. Kadere Marthias and Dr.Eve Esther Mugabi in Kampala Hospital, Kololo. Namajja Hailey Gabriela is the first born of Drs Kadere and Mugabi Eve.